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A Cane Toad is exhibited at Taronga Zoo August 9, 2005 in Sydney, Australia.

The cane toad, whose skin is toxic, has devastated the populations of some animals in Australia, where it is an invasive species.Credit: Ian Waldie/Getty

Cannibal cane toads’ rapid evolution

Invasive cane toads (Rhinella marina) in Australia have evolved a taste for their fellows, with tadpoles commonly devouring swathes of hatchlings. The behaviour evolved at a breakneck pace: in their native range in South America, the toads are far less cannibalistic, and they were introduced to Australia less than a hundred years ago. In 1935, farmers introduced the first 100 cane toads, and there are now well over 200 million of them — creating unusual competitive pressure from their own species. “These toads have gotten to the point where their own worst enemy is themselves,” says invasive-species biologist Jayna DeVore.

Nature | 5 min read

Fossil DNA hints at mysterious Toaleans

The 7,000-year-old skeleton of a teenage hunter-gatherer from Sulawesi in Indonesia might be the first remains found from a mysterious, ancient culture known as the Toaleans. Sulawesi has some of the world’s oldest cave art, but ancient human remains have been scarce on the island. The largely complete fossil of a roughly 18-year-old Stone Age woman was found in 2015, buried in the fetal position in a limestone cave. DNA extracted from the skull suggests that she shared ancestry with New Guineans and Aboriginal Australians, as well with the extinct Denisovan species of ancient human. The Toalean people, known only from scant archaeological evidence, such as distinctively notched stone tools, were thought to have lived in Sulawesi at around the same time.

Nature | 7 min read

Reference: Nature paper

Climate change and Europe’s deadly floods

Last month’s extreme rainfall in Germany and Belgium was made more likely by climate change, according to a modelling study by an international team of meteorologists. The deadly rains and subsequent flooding in the European region were between 1.2 and 9 times more likely to happen today than in pre-industrial times, and were 3–19% more intense, owing to climate change, the researchers found.

Nature | 3 min read

Reference: World Weather Attribution report

COVID-19 coronavirus update

News

Venezuelan COVID stats gathered in secret

Health-care workers in Venezuela are contributing to clandestine networks to collect accurate data on COVID-19 infections and deaths in the country. They say that Venezuela’s official numbers drastically undercount the real toll, because of a lack of testing and infrastructure and a deliberate effort by the government to downplay the pandemic. Medical staff in the country face a lack of basic medical equipment, a steady power and water supply, and adequate pay — and possible arrest if they speak out. “I always worry that we could get detained,” says an anonymous physician. “But I cannot live in a country where the official narrative is that everything is fine when we are living a totally different reality.”

Nature | 7 min read

Comment

Delays could make origin study impossible

The window of opportunity for investigating the origins of SARS-CoV-2 is closing fast, says a group of independent international researchers, convened by the World Health Organization (WHO) in October 2020 to join the joint WHO–China investigation. They argue that the process has stalled — and further delay will render some of the studies biologically impossible. They summarize the scientific process so far, and set out how to fast-track the follow-up scientific work required to identify how COVID-19 emerged.

Nature | 12 min read

Notable quotable

“Giving a booster to vaccinated people is not going to control Delta. What’s going to control Delta is vaccinating unvaccinated people.”

Vaccine researcher Anna Durbin says that COVID-19 vaccines are victims of their own success at preventing severe disease — if their efficacy wanes against new variants, people want a booster. (STAT | 6 min read)

Features & opinion

A boat using the sea-spraying cloud brightening system over the Great Barrier Reef in Australia during a 2021 trial.

During a field trial, a turbine generates plumes of seawater droplets that rise into the sky.Credit: Brendan Kelaher/SCU

Cloud-brightening test at Great Barrier Reef

In the world’s first field trials of marine cloud brightening, scientists have demonstrated a system designed to artificially brighten clouds to protect Australia’s Great Barrier Reef. On the back of a repurposed ferry boat, 320 nozzles spewed a mist of nano-sized salty droplets. In theory, the spray will be incorporated into low-lying clouds and make them reflect more sunlight, which would provide a bit of cooling shade for the coral colonies below. Field tests in March and last year gave researchers the chance to see the nozzles at work and observe how the mist behaved in the real world. If the project comes to fruition, it would require a vast array of misting stations to significantly affect the clouds over the huge reef — and would only buy time for more fundamental efforts to address climate change.

Nature | 11 min read

Holmes haunts female-led science start-ups

Female entrepreneurs launching hard-science start-ups say they are living in the shadow of failed blood-testing company Theranos and its disgraced founder Elizabeth Holmes. They talk of being constantly compared with Holmes and fending off questions about how their company will avoid a similar downfall — questions that most male founders don’t face. “There was already a higher bar before Theranos because we don’t fit the pattern,” says Falon Fatemi, who co-founded artificial-intelligence and media-distribution companies. “This just makes it that much harder.”

The New York Times | 7 min read (intermittent paywall)

News & views

Africa’s mountain forests sock away carbon

The high-altitude forests that gird Africa are unsung carbon sinks. The inaccessibility of African montane forests has hindered efforts to quantify the carbon stored by these ecosystems. Now, a survey of mature mountainside forest plots in 12 African countries fills this knowledge gap, and highlights the need to preserve such forests. “Anyone who has conducted field inventories in tropical mountains knows that measuring and identifying 72,336 trees, often just a few steps away from the void, is an amazing feat,” writes tropical ecologist Nicolas Barbier in his analysis of the research.

Nature | 6 min read

Reference: Nature paper